Process of making duplicate phonograph-records.



' PATENTED JUNE 4, 1907.

J. W. AYLSWORTH. PROCESS OF MAKING DUPLICATE PHONOORAPH RECORDS.

APPLICATION IILlBDlMAY 11. 1906.

Ts-SHEET 1.

AQ QMW PATENTED JUNE 4, 1907.

J. W. AYLSWORTH. PROCESS OF MAKING DUPLICATE PHONOGRAPH RECORDS.

' 2 SHEEN-SHEET 2.

. APPLIOATION FILED MAY 11. 1906.,

A Jiaveuidr:

umrnn STATES PATENT orrron.

JONAS W. AYLSWORTH, OF EAST ORANGE, NEW JERSEY, ASSIGNOR NEW JERSEY PATENT COMPANY, ()F W 1ST ORANGE, XEW JERSEY, A CORPO- RATlON OF NEW JERSEY.

PROCESS OF MAKING DUPLICATE PHONOGRAPH-RECORDS.

Specification of Letters Patent.

Patented June 4, 1907.

Application filed May 11,1906. Serial No. 316,250,

1'!) at whom, it may concern: 7

Be it known that I, JONAS W. Artswonrn,

a citizen of the United States, residing at 223 Midland avenue, East Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Processes of Making Duplicate Phonograph- Records, ofwhich the following is a description.

ass for making duplicate phonograph records, and my object is to provide a process for the purpose by which duplicate phonograph records may be produced at low cost, of superior quality, and whereby the percent age of im perfect records or discards obtained in actual manufacture will be very largely reduccd.

In the present development of the phonographic art, it is possible'to make matrices or molds which for all practical purposes are mathematically exact negative copies of the original master records, and several processes have been suggested and commercially used for obtaining duplicates from these matrices or molds. In a practical duplicating process, itis important that the temperatures used should not be too high, since the material from which the records are made contains- 0 considerable quantities of free stearic acid, which in the presence of a'high temperature attacks and roughens the surface of the mold, even when the latteriis protected by a nonoxidizing film ofgold or nickel. These molds 3 5. are very expensive and the slightest roughening is manifested in the reproduction from a record obtained from the same. Hence, it is important that the temperatures should be kept in the neighborhood of the melting 4o point of the material, orat best, only a few degrees above the same, in order that the life of the molds may be prolonged as much as possible. In working with the material at relatively low temperatures another difficulty is encountered, namely, the formation of air and gas bubbles, which appear on the surface of the record. These bubbles are-sometimes caused by the trapping of air in the mold, even when great care. is taken to avoid the difficulty, and some are caused by the decomposition of the material in its original manufacture, or when scrap material is remelted. The low temperature at-which the My invention relates to an improved proc-- material is worked makes it more or less viscid, and hence the bubbles do not have the opportunity of freely escaping, but move sluggishly through the mass.

By my present invention, I am enabled to produce duplicate records in a highly efficient and economical manner, the material being maintained in a molten state at. not necessarily more than a few degrees above the melting point, so as to prevent it from attacking and corroding the mold, while at thesame time, the operation, is such that air from appearing on the record surface.

To this end, the invention consists in making duplicate records by centrifugal force, the mold being rotated at a sufficiently high s eed and the molten material being introuced therein so as to be forced outwardly and distributed evenly around the entire bore of the mold, the mold being heated to about the temperature of the molten material, so that when the molten material is introduced therein, it will not chill on the -mold, but will retain its fluid state, thereby permitting its complete and uniform distribution to be effected and allowing all bubbles to be displaced and forced into or through the body of material. This forcing of the bubbles inwardly away from the surface of the record can be eil'ected rapidly and perfectly, since the tendency of the material to displace the bubbles, (provided the speed of rotation is high enough) may be made very much more decided than f the bubbles areallowed merely to float to the surface as at the present time. Consequently, by using centrifugal force, bubbles may be effectively forced back from the record surface even when such bubbles areso minute that their cosity of the material. Yet, these veryv mi nute bubbles which are due to decomposition Within the material are prominent enough to seriously affect the character of the reproduction. Having introduced the molten material in the rapidly turning mold, so as to uniformly distribute the material over the bore of the mold, it is of course important that the mold should continue to rotate until the materialbecomes hard enough to re tain its shape, but obviously the speed of r0- and gas bubbles are effectively prevented tendency to rise to the surface of the material is not sufiicient to overcome the natural v1station can be gradually reduced as the maif terial becomes gradually hardened.

It will of course be understood that the general principles of the invention can be which a practically continuous process can ;;-formed, all as I wi ,describe; and claim. fj'In the accompanylng drawings, forming part of this specificat on, 1 illustrate a con ,venient apparatus for thepurpose, said apparatus being simple in construction and cacarried out in many different ways, and in many difierent forms of apparatus. Preferably, however, the apparatus is one in pable of effective operation by comparatively unskilled labor.

Inthese drawingsFigure 1, is a side elevation, partly in section, Fig. 2, a cross-sectional view on the line 2-2 of Fig. 1, Fig. 3, a similar view on the line 33 of Fig; 1, Fig. 4E,

- a horizontal sectional view on the line 4 -4 perpendicular to the operated by a handle 9, -5

of Fig. 1, Fig. 5, a longitudinal sectional view of the mold showing-the end plates in position, and Fig. 6, an end View of the same illustrating the removable end plate.

In all of the above views, corresponding parts are represented by the same numerals of reference. p

Carried by a heavy substantial base 1 are the frames 2-2, rigidly connected at their upper ends by a top plate 3. Mounted between the frames 2 are rollers irl, arran ed in pairs and independently rotatable, so t at theymay turn at any desired speed. These rollers are not independently driven,

but, act merely as roller supports for the molds as the latter are rotated. The molds are rotated-by a series of'driving rollers 5-.5 having preferably rubber or fiber peripheries, sons to increase the friction on the mold. These driving rollers are carried by brackets 66 and normally occupy the position shown in full lines (Fig. 4.) so as to turn in a plane axis of the molds. By skewing the driving rollers from their normal position as shown in dotted lines (Fig. 4), the molds would not only be rotated as desired, but will be moved longitudinally, as will be understood, so as to engage with and be supported by the successive idler rollers 4cl, moving in this way from the left to the right of the machine in Fig. 1.

The skewing of the driving rollers is'effected by any suitable mechanism; for instance a rack bar 7, engaging toothed segments 8 on the bracket 6 of each roller and whereby all the roll- -ers will be moved axially." The driving rolla light elastic pressure.

so as to permit ers 5 are rotated by suitable mechanism,

shell as belts 10, engagingpulleys 11, carried bythe driving rollers and driven bypulleys 12 on the mam shaft '13. I illustrate the first two pulleys 12 at theleft as being of the same diameter so as to rotate the molds at the same speed during the first two stages of the operation, the succeeding pulleys being of gradually reduced dimensions, so as to rotate the molds at less speed. Provision'is made for cooling the molds after the material has been uniformly distributed therein, so as to effect a chilling and solidifying of the material, and for this purpose 1 illustrate a trough 14, located between'the idler rollers 4, beginning with the second set thereof, since of course the molds should not be chilled during the introduction of the material therein. 15 adapted to be normally pressed upwardly by asp'ring 16, so as to engage the molds with V The trough 14 is substantially filled with a loose absorbent material 17 ,such as fiber or sponge. Cooling water is admitted to the trough 14, through a perforated pipe 18, so as to always keep the absorbent material fully saturated.

The inlet and overflowpipes are connected by rubber sections 19, so as to permit the trough to be moved up and down into and out of engagement with the molds. The trough 14 is moved downwardlywhen the rollers are skewed to permit the molds to move longitudinally. This movement may be derived from the rack bar 7 by forming the same with cams 20, with which engage rollers on the rods 21., the latter being connected to the pivoted-arms 15. Obviously, as the rack bar 7 is moved to the right to skew the rollers, the trough 14 will be depressed so as to withdraw the absorbent material from contact with the molds. The molten material may be contained in a tank 22 heated in any suitable way as for instance,

by a steam coil 23. .Mouuted in the tank 22 is a simple form of pump 24-, the piston 25 of which is adapted to travel below an inlet 26, the molten material to enter the pump cylinder above the piston to thereby give always a definite charge of material, assuming the level of the latter, (shown in dotted lines, Fig. 1) to be constantly maintained. The pum 24 is carried on a'bar 27 mounted to turn in brackets 28 secured to the sides of the tank 22. When the molds are being successively introduced into the machine, the pump is swung rearwardly to occupy an inclined posit on, resting on the stop 29. At all times, t Wlll be observed that the pump cylinder 1S more or less 1mmersed in the molten material, so as to be effectively heated by the same, and thereby preventing congealing. w the pump comprises a nozzle 30, adapted,

when the pump cylinder s in a vertical posi- The discharge of tion, to enter the mold 31. These moldsare of any suitable type and are formed in any,

-or electrotyped, and with a removable end piece 33 attheother end, so that the molten material will be confined within the mold as the latter rotates. The removable and piece 33 fits the end of the mold very snugly, so as to prevent leakage 'of the molten mate.- point, and is locked in posit-ion in any suitable way. For instance, show the same as being formed with a series of cams- ,34, adapted to engage projections 35, formed on the mold, so that by inserting the end piece 33 in position, and giving it a partial turn, it will be locked frictionally firmly in place.

In carrying out my invention with apparatus of this general type, and assuming the tank 22 to contain the molten material (for instance the composition described in my I Patent No. 782,375 dated February 14, 1905) maintained at a temperature from 10 to 25 degrees above its melting point, I proceed as follows: The handle 9 is operated so as to swing the driving rollers 5 to or toward the position shown in dotted lines (Fig. 4) and one of the molds 3 being placed on the first set of idler rollers 4-4 and engaged by the corresponding driving rollers 53., will by the latter be turned at the desired high speed and at the same time will be moved longitudinally to the position shown in Fig. 1, The handle 9 is now returned so that the mold will be rotatedin this position. The pump 24 isnow swung to its vertical position and the plunger is elevated, carrying the charge of molten material and'discharging the same into the rotating mold, the temperature of which has been previously heated up to or preferably slightly a little more than the ten'iperature of the molten material. The molten material will, therefore, be distributed uniformly throu bout the mold and by reason of the centri igal force developed will be maintained in its liquid state and evenly disposed over the record surface, so as to take a very,

perfect impression therefrom. Since the temperature of the material is somewhat higher than its melting point, and since the mold is preferably at or about the same temperature, the material remains perfectly fluid during the time that it is being disposed over the record surface, and consequently ample opportunity is offered for dispa cing any bubbles, however minute, and forcmgthem radially inward. Even if these bubbles do not entirely escape through the liquid material, they are at least driven in from the record surface, which will therefore be perfect and freefrom bubbles. As soon as the charge of material has been delivered to the. molds, the

pump is swung rearwardly. The handle 9 is again operated to skew the driving rollers 5, and the mold with its charge of material therein will be advanced longitudinally so as to be engaged by the second driving roller and brought into position over'the second set of idlers. At the same time, a new mold is introduced over the first set of idlers and 'is filled with material, as explained. When the mold with its chargeof material therein has been thus advanced from the first section of the machine where the filling -operation takes place, it will, when normally rotated. by the successive driving rollers, be engaged by the cooling pad in the trough 14. These operations are repeated, the filled molds progressing step by steptoward the right of the machine and being rotated at successively reduced rates, as the material is gradually cooled and becomes solid. I prefer to dispense with a driving roller inconnection wit h the last set of idlers, at which point the material will be sufficiently solidified to retain its shape, the mold with its contents being then removed from the machine. The cap 33 is now removed and after the record has been contracted sufiiciently away from the bore of the mold, it is removed. By always introducing a fixed and definite charge of material into the mold, the necessity for reaming the bore of the finished duplicate records is done away with, although this operation can be performed if considered desirable. It will furthermore be seen that by using two end caps, the duplicate records will be finished at both ends when removed. from the mold. If it is desired to tapering bores, this may be effected by arranging the idler rollers 4 on an incline or by inclining the entire machine to a sufficient extent, whereby the material when intro duced into the mold, will accumulate to a greater extent at the lower end than at the upper end and will set in this position, after which the bore, if not straight, maybe finished by reaming, ora tapering bore may be entirely formed by a reaming operation, as will be understood.

' Having now described my invention, what I claim as new and desire to secure by Letters Patent is as follows:

v 1. The process of making duplicate records, which consists in rotating a hot mold at a high speed, and in introducing molten mate' rial therein, whereby the material. will be compressed by centrifugal force against the record surface and be uniformly distributed over the same, substantially as set forth;

2. The process 'of making duplicate records, which consists in rotating a hot mold at a high speed, in introducing moltenmaterial therein, whereby the material will be compressed byfientrifugal forceinto intimate engagement with the record surface, and in provide the duplicate records with cooling the mold andits contents While the mold is being continuously rotated, substantially as set forth.

' 3. The process of making duplicate records,

which consists-in rotating a hot mold at 'a high speed, in introducing molten material therem,' whereby the material will be com fined, substantially as set forth. o 5. The process of making duplicate records,

which consists in rotating a hot mold at a high speed, in introducing molten material therein, whereby the material will be compressed by centrifugal force into engagement with the record surface, in replacing the filled mold by an empty mold rotated at high speed, in continuing the rotation of the filled mold. and simultaneously applying a cooling medium to the same, and in introducing a charge of molten material into the empty mold, substantially as set forth.

6. The process of making duplicate records, which consists in rotating at a high speed, a hot mold having end plates, and in introducing within the mold a charge of molten ceases material, whereby the material will be compressed by centrifugal force into engagement with the record surface to form a duplicate record, Whose ends will be simultaneously finished, substantially as set forth.

7. The process of making duplicate records,

which consists in rotating at a high speed .a

hot mold-having end plates, and in introducing therein a fixed and definite charge .of

molten material which Willbe compressed by ,WhiCh consists in' rotating at a high speeds.

hot mold containing molten material whereby the material will be compressed by centrifugal force against the record surface and be uniformlydistributed over the same, substantially as set forth.

9. The process of making duplicate records which consists in rotating at a high speed a hot mold containin molten material whereby the material wifi be compressed by centrifugal force against the record surface and be uniformly distributed over the same, in cooling the mold and its contents so as to cause therecord to shrink with respect to the mold, and in then Withdrawing the record from the mold, substantially as set forth.

This specification signed and witnessed this 9th day of-May 1906.

- JONAS WV. AYLSVVORTH.

W'itnesses:

FRANK L. DYER. ANNA R. KLEHM. 

